Now that we are coming into an age of ubiquitous, it is expected that we are to be surrounded by many sensing nodes for recognizing our actions and circumstances. For example, IC and RF tags have come to be employed recently to track physical distribution of things. And, IT (Information Technology) devices used to recognize our actions and circumstances come to be able to respond to our requests autonomously while those IT devices have responded only when they are instructed so conventionally.
The technology for recognizing circumstances of an object uses recognition devices. Conventional general recognition devices are used only to recognize a single item, for example, faces and detect persons by using such single input means as cameras and implementing a single recognition algorithm in a single information processing device fixedly. In order to trace/manage a position and moving line of a person in a space, a plurality of such input means as cameras and information processing devices are disposed hierarchically to form an efficient processing apparatus, which is disclosed in, for example, patent documents 1 and 2.    [Patent document 1] Official gazette of JP-A No. 15981/1999    [Patent document 2] Official gazette of JP-A No. 306012/1995.
The present inventor et al have found that it is possible to provide services that are completely different from conventional ones by combining intelligent sensing nodes that can recognize images and voices, as well as perform intellectual processings so that those nodes can cooperate with each another to recognize the actual world.
Each of the IC and RF tags as described above can retain ROM data of only a few hundreds of bytes as a unique ID number consisting of a few hundreds of digits. Each node that is such simple in function can thus sense only part of information in the actual world. For example, conventional recognition devices as disclosed in the patent documents 1 and 2 have been used to achieve a single purpose such as detecting an object, a position of the object in a predetermined space, or the like, so that they are difficult to recognize circumstances of a target person to recognize not only the physical information in a space, but also the situation in the space with respect to the time axis.